Chennai: Researchers at IIT Madras have proposed implementing a rapid groundwater recharge technology for combined flood and drought mitigation near Ayankulam village in Thisayanvilai taluk of Tirunelveli District in Tamil Nadu. A proposal to study the agricultural well popularly known as 'Magic Well' in this regard has been sent to the district administration.
An open agricultural well in Ayankulam can recharge an estimated 1,500-2,500 litres of water every second for several weeks without overflowing. The recharge water for this well was from the excess overflow of an adjacent minor irrigation tank due to the record monsoon rains in Nov-Dec 2021. The well became a local attraction and was called a “miracle well” since typical wells would fill and overflow in a matter of hours at such recharge rates.
The region surrounding this village is considered a dry belt with hot summers. Many small land-holding farmers have abandoned their farming practices and work as labourers in larger farms or other labour-based occupations. Being close to the coastal zone, several agricultural and domestic wells in the region suffer from saltwater intrusion due to excessive pumping and lowering of groundwater levels. Even extending the agricultural water availability by a few months each year can positively impact the livelihoods of these farmers.
If accepted, the proposal could bring potential benefits to the region like preventing and reversing salt water intrusion, mitigate floods and droughts, distribute water equally throughout the region etc. Dr Venkatraman Srinivasan, Assistant professor, Department of Civil Engineering, IIT Madras, said, “This is a win-win situation for all stakeholders. The excess water which causes devastating floods and would otherwise empty into the ocean is being channelled to recharge the groundwater for storage and retrieval in the dry summer months.”
Talking about the "Magic Well", he further added, “The unique hydro-geology of the region allows the implementation of this rapid aquifer recharge. In most other places, wells do not sustain such high injection rates and would easily overflow.”
